Mobile machines such as haul trucks, scrapers, wheel loaders, and other types of heavy machinery are used to perform a variety of tasks. During the performance of these tasks, the machines often operate in conjunction with a limited resource, for example a loading machine such as an excavator or front shovel, or a processing machine such as a crusher or screen. When operating in conjunction with a limited resource, operation of a mobile machine relative to the resource and to other mobile machines competing for the same resource should be carefully managed to avoid machine collisions and to increase profit. The need to properly manage the machines can become even more important when the machines are autonomously controlled.
One attempt at managing operations of mobile machines relative to a limited resource is described in U.S. Pat. No. 5,586,030 (the '030 patent) issued to Kemner et al. on Dec. 17, 1996. In particular the '030 patent describes an autonomous vehicle system having a queue manager and a vehicle control system. The queue manager is configured to manage a fleet of autonomous dump trucks, and acts like a foreman assigning tasks to the trucks and tracking their progress as they perform the tasks The vehicle control system permits autonomous operation of each truck under the control of the queue manager.
When a truck of the '030 patent approaches a loader, the vehicle control system will communicate a queue position request to the queue manager, which will respond with a queue position based on a number of other trucks in the queue. The truck will then assume the assigned queue position. An operator of the loader will communicate a resource ready signal to the queue manager when it is ready to receive a truck from the queue. In response to this signal, the queue manager will allow a first truck in a first position in the queue to access the loader. When the first truck in the queue leaves the first queue position to access the resource, the truck will communicate a depart position signal to the queue manager. In response to the depart position signal, the queue manager updates the position of the next truck in the queue. As each truck moves, the process repeats until the position of every truck in the queue is updated. The vehicle control system knows the truck is approaching the resource as a result of detecting a queue trigger in the route being traveled. When the loader finishes loading the truck, the loader operator will cause a done signal to be sent to the queue manager, which will instruct the truck to leave the loader and resume following its route under fully autonomous control.
Although the system of the '030 patent may help manage trucks in conjunction with a common resource, the system may be limited. That is, the system of the '030 patent may do little to control spacing between trucks or reduce idle time of the resource between truck interactions.
The disclosed control system is directed to overcoming one or more of the problems set forth above and/or other problems of the prior art.